SMART REFRIGERANT
SELECTION FOR
ICE RINKS

Part II. What you need to know
about safety and health

EXECUTIVE SUMMARY
The global refrigeration industry is responding to a regulatory-driven transition
toward a new generation of environmentally sustainable refrigerant solutions. This
shift has major impacts on the private and community ice rinks, both large andsmall, operating in North America.
Part I of this white paper outlined the environmental, regulatory, cost, and energyefficiency considerations. Part II focuses on the safety, health, and operational
profile of common refrigerants used in rink chillers. This two-part white paper
provides the key facts decision makers need to select the best refrigerant option
for their ice rinks.

The content of this white paper is the sole responsibility of The Chemours Company.

Smart Refrigerant Selection for Ice Rinks: Part 2

EXECUTIVE SUMMARY (continued)
Apart from environmental, regulatory, and cost concerns, rinkowners and operators must also consider a range of health andsafety risks when selecting a refrigerant for an ice rink chiller
system. Risks such as toxicity, pressure hazards, and flammability
are associated with various refrigerants. These risks can be
managed with refrigerant selection, chiller-system design,
engineering controls, and other mitigation strategies.

While no refrigerant meets the definition of an “ideal” refrigerant,
there are refrigerants that can be safely and effectively used. Rinkowners and operators should select a product that best meetsthe desired safety and health profile, while still delivering theperformance, regulatory, sustainability, and cost requirements
addressed in Part I.

The “ideal” refrigerant would have the following healthand safety properties:• Nonflammable (safe for occupants and service
technicians and operators)• Nontoxic (safe for rink occupants in the event of leakor release)• Low operating pressures and temperatures (safe forservice technicians and operators)• No unusual or unexpected properties, handling, or
storage requirements• No negative environmental impact• No ozone depleting potential (ODP)• Low global warming potential (GWP)

2

Smart Refrigerant Selection for Ice Rinks: Part 2

Unpacking Health and Toxicity
Fundamental to toxicology is thesimple fact that the “dose makes thepoison.” All substances can exert toxic
effects at some dose or concentration;but, likewise, there are doses orconcentrations that do not produce
toxic effects.
For example, toxic effects have been observed for common
substances like table salt, oxygen, and water in very large
quantities, but their general safety is something demonstrated innormal everyday activities.
For rink owners and operators, there are two key groups ofpeople to consider. The first are the rink occupants (membersof the general population, such as customers, players, coaches,skaters, fans, and rink visitors). The second group consists of rink
operators and employees.

3Smart Refrigerant Selection for Ice Rinks: Part 2

Occupant Safety
Occupants are the most vulnerable to the potential health risksof short-duration exposures of high refrigerant levels—such asa leak due to a refrigerant system, piping, or component failure.
From this perspective, the preferred ice rink refrigerant would
have a low short-term health risk, including low risk of escape
impairment due to central nervous system effects or irritation ofeyes, nose, or lungs.

For rink occupants: Opteon™ XP40 and XP10
provide a safety profile better than other common
refrigerants (see ATEL data).

For rink occupants, it is the acute toxicity exposure limit (ATEL) thatis the appropriate “safe” concentration for members of the general
population.
R-717 (Ammonia)

Acute Toxicity
Exposure Limit

320 ppm

R-744 (CO2)30,000 ppm

R-134a50,000 ppm

R-22

59,000 ppm

Opteon™ XP10 (R-513A)

72,000 ppm

Opteon™ XP40 (R-449A)

100,000 ppm

R-410A

170,000 ppm

Other EscapeImpairing Effects

LOWEST RI SK > > > > > > HIGHEST RISK

RefrigerantEye, Nose, andRespiratory Irritation

None
None
None
None
None
None

Note: ATEL values are derived by the American Society of Heating, Refrigeration and Air
Conditioning Engineers (ASHRAE). The lower the exposure limits, the greater the short-termrisk for workers and occupants.

4

Smart Refrigerant Selection for Ice Rinks: Part 2

Worker Safety
Ice rink operators and employees should be protected against
adverse health effects from short-term exposures just like thegeneral public; but, in addition, a preferred ice rink refrigerant would
have low long-term health risk to protect workers from healtheffects associated with daily exposure to the refrigerant throughout
their lifetime.
Industry Standards and Workplace Exposure Limits
Refrigerants are classified by ASHRAE Standard 34 based on theirlong-term toxicity and flammability properties as indicated below.
Refrigerant Safety Classification per ASHRAE Standard 34
A:
Lower
Toxicity

B:
HigherToxicity

1 - No Flame Propagation

A1

B1

No LFL, based on modified
ASTM E681-85

2L - Lower Flammability

A2L

B2L

Burning velocity <10 cm/sec

2 - Flammable

A2B2

LFL <0.010 kg/m3 and heat ofcombustion >19,000 kJ/kg

3 - Higher Flammability

A3

B3

LFL <0.1 kg/m3 or heat ofcombustion >19,000 kJ/kg

Safety class A (lower toxicity) is reserved for refrigerants withoccupational exposure limit (OEL) values of 400 ppm and higher,
while class B is for refrigerants with OELs of less than 400 ppm.
While the cutoff value of 400 ppm is relatively arbitrary and should
not be viewed as a clear line between safe and unsafe refrigerants,
it is nevertheless used by code officials and designers to identify
and manage refrigerants with the highest potential to cause harmfrom long-term exposure.
For rink workers: Opteon™ XP40 and XP10 are both listed
by ASHRAE as class A1: nonflammable, low-toxicity
refrigerants.

5

Smart Refrigerant Selection for Ice Rinks: Part 2Hazards
Pressure Hazards
All chiller systems must be designed to operate safely for thepressures that will be encountered during normal operation as wellas unusual events, such as a power failure.

Lower GWP hydrofluoroolefin (HFO)
refrigerants operate at pressures similar
to today’s systems and do not present
any issues or hazards when compared tothe traditional hydrochlorofluorocarbon(HCFC-22) refrigerants being replaced.

CO2 can be safe to use, but these special considerations increasesystem-design costs. In addition, the need for service technicians
to receive additional training and be equipped with dedicated andappropriately rated equipment (e.g., gauges, recovery machines,hoses, etc.) is another requirement.
Other Unusual Hazards
A hazard unique to R-744 refrigerant is the potential to form dryice, a solid form of CO2, inside of a system under certain conditionsof temperature and pressure. It is important that every service
technician who works on an R-744 system be specifically trained tounderstand and safely deal with this unusual hazard that is uniqueto R-744 systems.

CO2 (R-744) systems operate at considerably higher pressuresthan traditional systems and must be designed for high-pressure
operation, including pressure relief devices and safe discharge
venting. Similarly, due to its pressure-temperature characteristics,
care must be taken to ensure liquid CO2 is never isolated in a pipeor line and allowed to warm up, potentially causing catastrophicline rupture.

6Smart Refrigerant Selection for Ice Rinks: Part 2Flammability
The flammability of a refrigerant is addressed through a number ofindustry standards, such as ASHRAE Standard 34. National andlocal building codes typically adopt these industry standards.
Flammability
ClassDesignation

R-717

2LLower Flammability

R-744

1

Nonflammable

R-134a1

Nonflammable

R-22

1

Nonflammable

Opteon™ XP10 (R-513A)

1

Nonflammable

Opteon™ XP40 (R-449A)

1

Nonflammable

R-410A

1Nonflammable

Refrigerant

In typical ice arenas, all refrigerants,including Opteon™ XP40 and XP10, arenonflammable, except ammonia (R-717),
which is classified by ASHRAE as class
2L: mildly flammable.

The flammability of ammonia (R-717) requires it to be confined toonly locations where the flammability hazards can be managed,such as outdoors or in a machine room with controlled accessand dedicated and appropriately rated equipment. While the toxic
properties of ammonia typically dominate discussions of its use asa refrigerant, the fact that it is flammable should not be ignored.
In system retrofits, where a new refrigerant replaces an existing
refrigerant, such as R-22, rink owners and operators should notethat the new alternative should be of the same flammability class as
the original product.
While the industry continues to drive to lower GWP refrigerants, atsome point flammable refrigerants may become part of the solution.
Fortunately, there are several mildly flammable (A2L), low toxicity
products in development based on HFO technology. These will
avoid the need for highly flammable or explosive (class 3) risks like
R-290 (propane); they’re also safer from a toxicity standpoint than
R-717 (ammonia).

7

Smart Refrigerant Selection for Ice Rinks: Part 2Conclusion
With excellent short- and long-term safety and health profiles, aswell as low GWP and zero ODP, HFO refrigerants are becoming apopular choice. While they may not be the only solution for every
application or system, HFOs are excellent choices for rinks looking
to achieve long-term compliance with an optimal balance ofperformance, safety, and cost.
As leaders in the refrigeration industry for nearly 100 years,
Chemours and our original equipment manufacturer (OEM) andmechanical partners are here to answer all your questions andhelp you navigate through this transition. Please reach out to us
through your local Chemours contact or at optforbetter.com/nhl.

8

Smart Refrigerant Selection for Ice Rinks: Part 2Appendix
Safety Classification and Standards
It is important to keep in mind that occupational exposure limits(OELs) are used to maintain safe workplace concentrations
to protect workers over their entire working lifetime. It is not
appropriate to use the OEL to assess the safe use of refrigerants
in the general population, as the general population is potentially
exposed via accidental refrigerant releases and for intermittent
or short periods of time. In other words, the acute toxic exposure
limit (ATEL) is the appropriate “safe” concentration for members of
the general population exposed to refrigerants, and the OEL is theappropriate “safe” workplace concentration.

R-717 (Ammonia)

The table at right provides short-term toxicity data that is thebasis for establishing the safe refrigerant concentration in an
occupied space.
When calculating a substance’s ATEL, the focus is on acutetoxicity with attention to lethality, cardiac sensitization, anestheticeffects, and other escape-impairing effects. While it would not bemeaningful to make decisions on refrigerant safety based on minor
ATEL differences, refrigerants with relatively low ATELs should becarefully assessed for health effects before selection. The table atright provides an illustration of the range of ATEL concentrations(short-term concentrations “presumed safe”) documented in
ASHRAE Standard 34 and ISO817.

Short-Term ToxicityAcute Toxicity
Exposure Limit(ASHRAE 34)

Acute Toxicity
Exposure Limit(ISO817)320 ppm

320 ppm

R-744 (CO2)30,000 ppm

30,000 ppm

None

R-134a50,000 ppm

50,000 ppm

None

R-22

59,000 ppm

59,000 ppm

None

Opteon™ XP10(R-513A)

72,000 ppm

72,000 ppm

None

Opteon™ XP40(R-449A)

100,000 ppm

100,000 ppm

NoneR-410A

170,000 ppm

170,000 ppm

None

Refrigerant

Other EscapeImpairing Effects

Eye, Nose, andRespiratory Irritation

9Smart Refrigerant Selection for Ice Rinks: Part 2

Safety Classification and Standards(continued)
Long-term toxicity safety for workers is generally described interms of OELs. OELs are exposure concentrations averaged overan eight-hour workday that are designed to protect healthy workers
throughout a working lifetime.
The table at right provides an illustration of the range of OEL
concentrations (i.e., long-term, workplace concentrations thatare “presumed safe”) documented in ASHRAE Standard 34 andISO817. There are two safety classifications for refrigerants, A andB, where safety class A (lower toxicity) is reserved for refrigerants
with OEL values of 400 ppm and higher, while class B is forrefrigerants with OEL values lower than 400 ppm.
OELs are not appropriate for use in conducting health safetyassessments for short-term exposures or any exposures involving
the general population. OELs have several sources, such as theworkplace environmental exposure level (WEEL), threshold limit
value (TLV), and permissible exposure limit (PEL). All the mentioned
OELs are set using similar processes, but they originate fromdifferent organizations. ASHRAE and International Organization forStandardization use OELs to assign safety classifications.

Long-Term ToxicityRefrigerant

R-717 (Ammonia)

Occupational Exposure
Limit (OEL)ASHRAE
Safety Class

25 ppmBOpteon™ XP10 (R-513A)

650 ppm

AOpteon™ XP40 (R-449A)

830 ppm

AR-410A

1,000 ppm

A

R-22

1,000 ppm

A

R-134a1,000 ppm

AR-744 (CO2)5,000 ppm

A

10

The information set forth herein is furnished free of charge and based on technical data that Chemours believes to be reliable. Chemours makes no warranties, expressed or implied, and assumes
no liability in connection with any use of this information. Nothing herein is to be taken as a license to operate under or a recommendation to infringe on any patents or trademarks.
©2018 The Chemours Company FC, LLC. Opteon™ and any associated logos are trademarks or copyrights of The Chemours Company FC, LLC. Chemours™ and the Chemours Logo
are trademarks of The Chemours Company.
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